‘She’s got the courage, the compassion, and the heart to get the job done,’ Barack Obama said of Hillary Clinton.
Photograph: Alamy

Barack Obama launched a coordinated push to unify Democrats against Donald Trump on Thursday, formally endorsing Hillary Clinton for the first time after a conciliatory meeting with her primary opponent Bernie Sanders.

In a rapid sequence of events in Washington that contrasted with renewed rancor among Republicans, Sanders emerged from the Oval Office peace talks with the president to say he was now prepared to meet Clinton and work with her after losing Tuesday’s primary elections.

“I spoke briefly to Secretary Clinton on Tuesday night and I congratulated her on her very strong campaign,” the Vermont senator told a throng of reporters outside the West Wing. “I look forward to meeting with her in the near future to see how we can work together to defeat Donald Trump and to create a government that represents all of us and not just the 1%.”

But within an hour the meeting was upstaged by Obama’s own, more emphatic endorsement of his former secretary of state, which was confirmed in a video released by the Clinton campaign.

“I’m with her,” said Obama, in remarks recorded on Tuesday. “I don’t think there has ever been someone so qualified to hold this office,” he added, in pointed contrast to a claim made by Sanders in April.

“She’s got the courage, the compassion, and the heart to get the job done … I have seen her judgment,” said the president. “I’ve seen her toughness. I’ve seen her commitment to our values up close. And I’ve seen her determination to give every American a fair shot at opportunity, no matter how tough the fight – that’s what’s always driven her, and still does.”

Despite Sanders insisting he would still compete in the last primary election in Washington DC next Tuesday and fight for his policies to be adopted at the party convention next month, the growing thaw was underscored by the Vermont senator in separate meetings with Joe Biden and the Senate minority leader, Harry Reid.

Reid told reporters after their sit-down that he had invited Sanders to address the Democratic caucus next Tuesday at its weekly luncheon. The Nevada senator also said he believed Sanders had accepted that Clinton is the nominee and should be given the opportunity to make his own decision on how to proceed. “I’m in a good place with Bernie … I’m not pushing him to do anything,” Reid said.

In an interview with the Boston Globe, Warren said: “I’m ready to jump in this fight and make sure that Hillary Clinton is the next president of the United States and be sure that Donald Trump gets nowhere near the White House.”

She described Clinton as “a fighter, a fighter with guts”, while stressing to MSNBC’s Rachel Maddow that Bernie Sanders’s campaign had also been “powerfully important” in bringing millions of people into the democratic process.

Appearing on MSNBC, Warren was asked by Rachel Maddow: “If you were asked to be Secretary Clinton’s running mate, do you believe you could do it?”

Her response was concise: “Yes, I do.”

Even Martin O’Malley, who dropped out of the contest with Clinton in February after he was eclipsed by the growing popularity of Sanders, joined in on Thursday with his own endorsement.

Obama and Clinton are due to appear at a rally together next Wednesday in Wisconsin, a blue-collar battleground targeted by Trump.

Republicans have sought to portray Obama as a liability, often referring to the prospect of Clinton taking over the White House as the president’s third term. But polling indicates Obama could well be a boon for Democrats, with an approval rating that crept just past 50% this month.

Obama had until now remained on the sidelines during the Democratic primary, lending praise to both Clinton and Sanders throughout the contest but maintaining an aura of caution. The president was nonetheless widely expected to endorse Clinton and last met privately with his former secretary of state in December at the White House.

Once bitter rivals in the 2008 Democratic race, Obama and Clinton went on to develop a closer rapport often reflected in a public showing of admiration for each other.

In a podcast with Politico earlier this year, Obama said he had gotten to know Clinton well in recent years and confessed that the media was “a little unfair to her” in their bruising primary eight years ago.

“She is a good, smart, tough person who cares deeply about this country,” Obama said, while adding that Sanders had benefited in part from being relatively new to the public eye.

Despite his neutral posture, the president has been visibly eager to engage in the presidential contest, often issuing sweeping condemnations of Trump over his sharp rhetoric against immigrants and Muslims. The president also routinely took shots at other Republican contenders, and has shown little reluctance in criticizing party leaders in Washington for pushing policies that gave rise to Trump’s success.

He will probably carry a similar message forth on the campaign trail, as members of the president’s staff determine how best to assist Clinton in the coming months. Obama’s own re-election campaign in 2012 was boosted significantly by the presence of Bill Clinton on the stump, most memorably when the former president delivered an electrifying speech that stole the show at the Democratic convention in Charlotte, North Carolina.

Hillary Clinton, while campaigning across the country, has largely embraced Obama’s record and speaks often of the need to build upon his administration’s progress. She has distanced herself from the president on just a handful of issues, such as trade and Obama’s response to the Syrian civil war.

The White House press secretary, Josh Earnest, claimed “there is a lot of agreement about the way forward” among Democrats after Obama’s meeting with Sanders, but insisted no one “had the expectation that he was going to deviate” from a plan to still contest the DC primary.

In his speech following the White House meeting, Sanders also made concessions to some of his supporters, who remain angry at aspects of the primary process, including a suggestion that Tuesday’s primary election in California had overstated the size of Clinton’s victory.

“I look forward to the full counting of the votes in California, which I suspect will show a much closer vote than the current vote tally,” said Sanders, who noted he also would “of course be competing in the DC primary” next Tuesday.

But Sanders pointedly thanked Obama and Biden for the “degree of impartiality they established” during the primary, and made no mention of his previous aim to convert Clinton-supporting superdelegates to his side.

“They said in the beginning that they would not put their thumb on the scales and they kept their word and I appreciate that very, very much,” said the Vermont senator, who has been highly critical of other party leaders.

Though declining to take questions from reporters, Sanders appeared to show evidence of a campaign coming to terms with its election defeat but eager to take full advantage of the phenomenal support it has demonstrated for previously neglected issues.

“Our campaign has been about building a movement which brings working people and young people into the political process,” Sanders told the dozens of reporters and presidential staff watching from nearby offices after one of the most eagerly awaited White House meetings in recent years.

Obama walks with Bernie Sanders during their meeting at the White House in Washington on Thursday. Photograph: Michael Reynolds/EPA

“[We want] to create a government that represents all of us and not just a handful of wealthy campaign contributors. We will continue to do everything we can to oppose the drift that currently exists towards an oligarchic form of society in which a handful of billionaires exercise enormous power over our political, economic and media life,” he added.

Campaign aides, who have been meeting at his Vermont headquarters over the past 24 hours, say he has a firm list of objectives that he wishes to see put on the platform during the convention in Philadelphia.

“These are some of the issues that many, many millions of Americans have supported during my campaign. These are the issues that we will take to the Democratic national convention in Philadelphia at the end of July,” the senator said.

Sanders is due to host a rally in Washington later on Thursday evening, in which he said he would campaign for the District of Columbia to receive full statehood rights, but he also stressed that the key challenge for Democrats now was uniting to make sure they won the presidential election.

“Donald Trump would clearly to my mind, and I think the majority of Americans, be a disaster as president of the United States,” said Sanders.

“It is unbelievable to me that the Republican party would have a candidate for president who in the year 2016 makes bigotry and discrimination the cornerstone of his campaign.”